Electromagnetically controlled switch



Sept. 14, 1948.

H. J, HAMMERLY ELECTROMAGNETICALLY CONTROLLED SWITCH 5 Sheets-Sheet 1 Fled Oct. 24, 1942 NJEW "Sept 14, 1948- I H. J. HAMMERLY 2,449,221

ELECTROMAGNETICALLY CONTROLLED SWITCH Filed Oct. 24, 1942 3 Sheets-Sheet 2 INVENTOR 13 )[erzafI/.Ijz/W ITT Patented Sept. 14, 1948 ELECTROMAGNETICALLY CONTROLLED SWITCH Herman J. Hammerly, Plainville, Conn., assignor to The Trumbull Electric Manufacturing Company, Plainvilie, Conn., a corporation of Connecticut Application October 24, 1942,l Serial No. 463,215

14 Claims. (Cl. 20G-'104) My invention relates to electric switches o! the type which is usually controlled from a distance and held closed magnetically. The main object is to provide a compact form of such device which is protected against tampering with the contacts when the circuit is closed.

Another object is to provide such a device in which the main switch body which carries the movable switch member and the magnetic control coil are readily separable.

Another object is to provide a "hold-in switch device in the magnet coil circuit which must be opened before access can be' had to the switch contacts and terminals.

Another object is to provide a device in which the circuit terminals are all carried by one block and the switch unit by another block which is readily removable from the terminal block.

Fig. 1 is a side view and partial sectionof one form of device embodying my invention.

Fig. 2 is a front view and partial section of the same.

Fig. 3 is a plan view and partial section of the same.

Fig, 4 is a cross sectional view on the plane of the line 4-5 of Fig. 2.

Fig. 5 is a front view of the main insulating block with contacts and terminals, the switch unit being detached.

Fig. 6 is a rear view of the switch unit per se.

Fig. 7 is a side view and partial section of the parts shown in Figs. 5 and 6 showing their relative positions ready for connection. This also shows the switch unit provided with a handle for convenience in handling.

Fig. 8 is a diagrammatic view showing the conducting parts oi the mechanism in the open circuit position.

Fig. 9 is aside view of an electro magnetic controller enclosed in a receptacle.

Fig. 10 is a perspective view oi parts of the hold-in switch and the disconnecting contacts.

Fig. 11 is a fragmentary detail view showing hold-in and disconnecting switch parts Inthe normal operative position.

Fig. l2 is a similar view but with the hold-in and disconnecting switch parts in the position they occupy as the main switch unit is in position to be removed by simply drawing it out.

The form shown herein embodies certain features of the switch mechanism of my Patent 2,295,577 issued September 15, 1942, having line terminals I0, I3 and I0' and load terminals II, I I and I I and the main movable switch members I2. I2, I2 each adapted to coact with` station- `I5 by a link'l and lever 29. The slide carries a spring pressed cross conductor I3 which constitutes the movable switch member of the holding-in contact device or second switch-having stationary contacts 20 and 2| with terminals I'I and 22 respectively. The switch member I9 is l mounted in a slot I3' in the slide I5 and pressed by a spring I3" lwhich is also mounted in. said slot. (See Fig. 4.) It will be noted that the ends ci the contacts 20 and 2I are offset beyond the plane of the anchorage portions so that the cross piece I8 need be moved upwardly only a short distance in order to break the circuit. Start and stop switches 23 and 24 are connected to the terminals I1, 22 and I0 as shown in Fig. 8.

The frame 25 ofthe coilv I5 and the insulating base or block 23 which carries the terminals I 0, I0, I0', II, II, II, Il and 22 are both supported on a channel member 21. A layer 23 of insulation may be interposed between 23 and 21. The lever 29 hinged at 30 has one end connected by a link 3| with the armature core I8 of the magnet and the other end forked to engage the projection I 5' on the slide I5. A spring 3| affords a resilient abutment between the .lever and the armature.

The switch unit or assembly per se has an insulating block 33 in which the contact carrier I5 slides. One or more springs 34 biases the slide and the switch members I2, I2 toward the open circuit position. Studs or conductor jacks 35 and 35" are secured in the block 33. The front ends Hand I4 c onstitue the contacts for the movable switch members I2. The rear ends of the studs are headed or enlarged and constitute extension contacts engaging the spring contact .extensions 33 and 3l which are connected tothe terminals I0 and II respectively.-

The block 2B has a passage 33 to permit the slide I5 and its projection I5 and the holding-in switch member I 3 to pass through and connect with the forked arm ofl lever 23 and thecontacts 20, 2|- respectively. It also has a key-.hole like passage 39 in line with each of the contact portions 3'3, 31 adapted to receive the headed end of a stud 35 so that the switch unit may be applied to the base and then slid downwardly to interlock with the base block 23.

The stationary contact 31 carried by the base 3 and the stud contact Il carried by the block u constitute what may be termed the third or disconnect switch.

The block 33 preferably has a front plate Il to cover the movable switch members il and a back plate 4| to cover the terminals il and Il when the switch unit is in place. Screws I2 may connect the parts 33, 40 and Il.

The coil control circuit being of low voltage, the holding-in switch contacts il, 2l and 2i need not be of any special design to resist arcing. Wh'en assembling the switch unit on the base it is simply applied with the ends of the studs Il, 35 in line with the enlarged upper ends of the key-hole slots 39. The unit is then pressed inwardly until the studs 35, .3l engage the contact extensions 38 and Il of the terminals il and Ii and then slid downwardly. The magnet being, of course, de-energized the upper end of the lever 28 will be pressed forwardly against the base so that the projection Il' on the contact slide carrier I! can pass behind it when the switch unit is pushed in and slid down into place. In detaching the switch unit the reverse action takes place. When the switch unit is moved to the off" position the carrier i! is freed from control of the magnetic actuator so that the springs 34 are free to move the carrier it `and the main switch contacts to the open circuit position even if the movable parts of the actuator should become stuck and fail to return to the o position when the magnet is de-energized. This is an additional safety precaution.

The device will ordinarily be enclosed in a suitable box or receptacle 4l having a hinged cover 85 4l. When the cover is closed the switch unit can not be detached from the base. The detachable switch unit may have a, projection or handle 43 to facilitate attachment to and removal from the terminal block by manually sliding the switch unit down or up as the case may be.

It will be seen from the foregoing that the circuit terminals are all fully guarded when the switch unit and its holding-in contacts are in place. The circuit must be killed either from the remote control location of the start-stop switch or by removing the switch unit per se before work` can be done on the contactor parts. The main circuit is automatically broken by the simple act of removing the switch unit. After the switching assembly has been removed al1 of the terminals are exposed for wiring.

The upward sliding motion of the switch unit not only breaks the electrical connection but the mechanical connection as welL It will also be noted that the switch unit has two possible positions on the base, i.v e. the lower position in which the parts are all interlocked and the upper position, and that from the latter position the switch unit may be pulled out and removed provided the cover or other preventive means is first removed. The contacts 20 and 2l are so proportioned and mounted relative to the cross connection Il that the holding-in circuit is broken at the beginning of the movement of detaching the switch unit and before the load circuit is broken. At this stage the studs or jacks 35 and 35' are still in engagement with the contacts Il and 31 so that the release of the magnet will open the main load circuit within the switch base at the contacts i2, Il and I4. In other words the same switch members take the arcing load whether the circuit is broken by manual or automatic means.

I claim:

circuit terminals mounted thereon and having extensions within the base, said base having keyhole shaped openings in alinement with said extensions, a detachable switching assembly unit consisting of an insulating block, contacts and cooperating switch members mounted within said block, studs having one end of each embedded in said block to be engaged by one of said switch members, the opposite ends of said studs projecting from said block to engage extensions in said base and having enlarged heads adapted to interlock with said base within said openings for holding the unit on the base.

2. An electromagnetic controller comprising a base, an electromagnetic actuator carried by the base including a coil, a main switch, a body carrying said main switch detachably carried by the base, a holding-in switch device in circuit with the coil of the magnetic actuator partly carried by the base and partly by the detachable body, said body being slidable on the base from a position in which the main switch circuit is closed and to another position in which the main switch is open.

3. In a switch, a support, a magnet having an armature and a lever connected to the armature, a switch unit having an insulating body, means for detachably connecting the body to the support, hold-in contacts carried by the support and connected in circuit with the magnet coil, a carrier slidable in the body and carrying a switch member for engaging the hold-in contacts, said carrier having a projection for slidably engaging the lever on the support.

4. In an electromagnetic switch, a magnet having a lever hinged at one end and movable backward and forward, a switch unit comprising an insulating body having stationary contacts and a slide carrying a movable switch member, a stationary insulating base carrying circuit terminals and having conductors connected with the terminals, studs carried by said body and electrically connected to its stationary conductors, said base having slots through which said studs can be inserted to engage the conductors on the base and interlock the switch unit with the base, said slide having a projection connected with the end of said lever when the studs engage the conductors on the base and the switch unit is interlocked with the base.

5. In an electromagnetic switch, an electromagnet coil, a magnetically movable lever, a switch unit comprising an insulating body having stationary contacts and a slide carrying a movable switch member, a stationary insulating base carrying circuit terminals and having conductors connected with the terminals, headed studs carried by said body and'electrically connected to its stationary contacts, said base having key-hole slots through which said studs can be inserted to engage the conductors on the base and interlock the switch unit with the base, said slide being operatively connected to said lever when the studs engage the conductors on the base, stationary hold-in switch contacts on the base in circuit with the magnet coil and a switch member carried by the slide engaging the hold-in contacts 4 when the switch unit is interlocked with the base and the circuit is closed through the main contacts.

6. In an electromagnetic controller, a base carrying the circuit terminals and an electromagnet and armature, an insulating block slidably 1. In an electric switch, an insulating base, connected with saidbase carryingstatiomry and movable switch mechanism and means for connecting the movable switch mechanism with the amature by sliding the block in one direction on the base and means for interlocking the block to the base in at least one position of the block.

7. In an electromagnetic controller, an insulating base, an insulating block detachably connected thereto, an electromagnet coil, an armature and an actuating member carried by the base, a main switch carried by the block and having a movable switch member detachably connected to said actuating member and adapted to be held in closed circuit position by the magnet, armature and actuating member when the coil is energized, a hold-in switch adapted to be connected in circuit with the magnet coil when the coil has been energized and means for opening the circuit through the hold-in switch and the magnet coil when disconnecting the block from the base.

8. In a combined magnetically and manually operated switch a. base carrying an electro-magnet with an armature movable between two positions in response to energization and deenergization of the magnet coil, a switching contact assembly having contacts and bodily movable betweena position where the contacts are under mechanical control of the armature to open and close the load circuit in response to the movement of the armature and another position where the contacts are free from mechanical control by the armature, means for moving the contacts to open circuit position when they are free from mechanical control by the armature, a handle for manually moving the contact assembly to one or the other of its two positions, and means for mechanically holding said base and contact assembly together while in either of their relative. positions. i 9. An electromagnetic controller comprising an electromagnetic actuator having a movable member, a base supporting said actuator, a switch assembly having a movable switch member detachably lconnected with the movable actuator member, means for slidably connecting said switch member with said base and interlocking said movable switch member with said movable actua.

tor member and means for breaking the circuit through said switch assembly before it is possible to remove said assembly from said base.

10. A combined magnetically and manually operable controller for line and load connectors comprising an electromagnet with its armature and energizing coil, a base therefor, a manually movable switch assembly having stationary and movable contacts and a carrier for the movable contacts, means for detachably mounting the switch assembly on the base with the stationary contacts connected to the line and load terminals which supply the energy to the coil, means for detachably connecting the carrier to the armature so that the carrier is disconnected from the armature when the switch assembly is detached from the base and a hold-in switch in the coil circuit when the switch assembly is 'connected to the base. said hold-in switch having contacts carried by the base and a movable switch part carried by said carrier, said hold-in switch parts being so mounted with respect to the connections between the switch assembly and the base that the circuit through the hold-in switch is broken before the connections from the stationary contacts of the switch `assembly are broken.

1i. In a combined magnetically and manually operated switch, a base carrying an electro-magnet coil with an' armature movable between two positions in response to low voltage energization and deenergization of the magnet coil, a switching assembly having load contacts and bodily movable between a position Iwhere the contacts areunder mechanical control of the armature to open and close a load circuit in response to the movements of the armature and another position where the contacts are free from mechanical controlby the armature, wiring terminals on the base for connection of the low voltage magnet voperating circuit and for the load circuit, means for moving the load circuit contacts to open circuit position upon deenergization ofthe magnet coil and also when the contacts are free from mechanical control by the armature, a handle for manually moving the switching assembly to one or the. other of its two positions, a low voltage contactI for breaking themagnet coll circuit at the start of the movement -of the switching assembly from its armature-controlled to its armature-free position, and means for mechanically and electrically connecting said base and switching assembly together while in either of their relative positions, said means preventing removal of the assembly from the base excepting when the assembly is free from mechanical or electrical control by the armature and the load circuit is therefore open. 12. Apparatus of the character described, comprising two switches having a common operator, one switch being of the plural circuit type having movable contacts and relatively stationary contacts, an insulating block carrying said contacts and having connectors, said stationary contacts being mounted on said connectors, an insulating base having terminals with extensions engaged by said connectors when the block is in place on the base. the second switch consisting of stationary contacts mounted on the base and a movable bridging contact, a slide mounted in said block carrying the movable contacts of both switches, an electromagnet having an armature actuated member for actuating said slide and means for detachably connecting the block to the base and the armature actuated member to the slide by a sliding movement of the block.

13. In an electromagnetic switch, an electromagnet, a support for said magnet having main line and load terminals and remote control terminals, each terminal having a conducting extension, a switch assembly having an insulating block slidably connected with the support and having switch contactscarried by it, a carrier slidable in said switch block and having a switch member carried by it and adapted to engage the contacts carried by said block, said latter contacts having conducting members adapted to slidably engage conducting extensions carried by said support which are associated with the main line and load terminals, said block also carryinga bridging member coacting with the conducting extensions which are associated with the remote control terminals, and means actuated by said magnet for actuating said carrier, said block being manually slidable to open the circuit through said bridging member and also to separate the conducting members associated with the switch contacts of the block from the extensions associated with the main and load` terminal extensions. A

14. In an electromagnetically actuated switch having means for disconnecting the switching members, the combination of a support having main line and load circuit terminals and termi- 7 nals for a hold-in circuit, each of said main, load and hold-in circuit terminals having an electric conductor extension carried by said support, an insulating block siidably connected with said support, switch contacts carried by said block, a carrier slidable in said block, switch members carried by said carrier for coacting with said contacts, electric conductor connectors carried by said block connected to and extending from said switch contacts and slidable with said block to engage with and be disengaged from the extensions of the main line and load circuit terminals, a hold-in bridging member carried by rand slidable -with said block for connecting the extensions.J

of the hold-in circuit terminals when said block is in the on" position on said support and an electromagnet and spring actuated means for moving said carrier and said switch members to Iopen and close the main line and load circuits, said hold-in circuit including the circuit of the electromagnet and being broken by the sliding or the block from the on to the "oft" position,

HERMAN J. HAMMERLY.

. 8 americas crrnn The following references are of record in the file of this patent: 

